HID: lg-g15 - Add support for Logitech G13.

HID: lg-g15 - Add support for Logitech G13.

The Logitech G13 is a gaming keypad with general-purpose macro keys,
four LED-backlit macro preset keys, five "menu" keys, backlight toggle
key, an analog thumbstick, RGB LED backlight, and a monochrome LCD
display.

Support input event generation for all keys and the thumbstick, and
expose all LEDs.

Signed-off-by: Leo L. Schwab <ewhac@ewhac.org>
Reviewed-by: Hans de Goede <hansg@kernel.org>
Tested-by: Kate Hsuan <hpa@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>